I've never been interested in motherhood. I never planned how many kids I would have or by what age I would have them. I don't have an ironic, old-fashioned name picked out for a boy, or a hipsterish androgynous option for a girl. In my college years and early 20s, my peers and I were more concerned about finding a career, a boyfriend and an apartment in New York City with a dishwasher and an AC unit. Baby ambivalence seemed normal. Kids weren't on anyone's radar.

Well, maybe they were a little. During my senior year in college, a friend and I were playing a morbid rendition of that game Would You Rather? As in, Would you rather lose your sight or hearing? Gain 50 pounds or sprout a permanent layer of hair on your chest? Never be able to have an orgasm again or never be able to have children?

I'd laughed about the last one. "Too easy. Never be able to have children."

We'd been lying on the floor of the living room, flipping between Law & Order: SVU and Project Runway. My friend had rolled over and studied my face, wrinkling her brow as though she were annoyed, suspicious even. I knew I could be too cavalier, too hotly opinionated for her liking at times. "I would be absolutely devastated if I couldn't have children," she said, tartly.

"Really?" I scrunched my nose in disapproval. To me, people who needed children to have a full and rich life were provincial, unoriginal. "It wouldn't bother me."

I may be genuinely averse to tiny humans, but in college, still in rehearsals for adulthood, I believed that my position on kids said something fundamental about me before I could get out there and prove it in the real world—that I was independent, ambitious. I understood children made life harder. I wasn't so naive as to believe they completed a fairy tale. Anyone could be a mother, but it took skill, talent and tenacity to make it in New York City, which was where I planned to move immediately after graduation.

Of course, it's easy to declare your bold stance on children when they're a very long way off and the window of opportunity is wide open rather than closing. I'm 30 now, and my husband is 36, hanging on to the same fence that I am. ("If you want them, I want them. If you don't, I don't." Thanks.) He's unburdened, the way men get to be, by the threat of regret. With so many of our friends embracing this next stage of life, my baby ambivalence—really, our baby ambivalence—is suddenly pronounced, glaring and a bit suffocating. I'm not as cool and unconventional as all my posturing suggests, and I am terrified of waking up one day in my late 40s, mourning my decision to go child-free but unable to do anything about it.

This fear of regret is not new. Two conflicting streams have always run through me—I don't want kids, but I don't want to regret not having kids. I'd banked on desire and biology meeting eventually, a confluence where the two warring ideologies would merge. I didn't ever expect to turn into mush, melted by the sight of a babbling, cherubic bundle, but I thought maybe I'd see a cute young dad playing dress-up with his daughter and at least feel warmth in my heart. Maybe I'd even envision my husband, who would be a great father because he's patient and kind, in that frothy pink tutu, making our daughter shriek with laughter while he pirouetted around and around.

Something similar happened to my mother, who never thought she would have children either. She was married to my father for seven years before she got pregnant with me at 30. That may seem run-of-the-mill now, but it was somewhat atypical for a woman of her generation to wait as long as she did to have a child, and to prioritize her education and career (in the demanding, male-dominated world of finance, no less). My father once told me that he felt bad for her, because she had few female friends who could relate to her ambition and drive. "We would go to parties," he told me once. "And I would see your mother in the corner, trying to make conversation with the stay-at-home mothers. She had little in common with many women her age, and it could be lonely for her."

My mother's feelings about children changed when her sister had her first child. "We were driving home after meeting your cousin," she told me, "and I was suddenly consumed with the urge to have a child. I turned to your father and said, 'I want one.'"

What I want is for this to happen to me.

But. A few friends have admitted that getting pregnant was the antidote to an unfulfilling career that seemed to have flatlined. Around 30, when you become disillusioned with your professional life, you can actually get excited and feel purposeful about a baby. I am far from disillusioned with my career. I am doing what I always wanted to do, and in spring 2015, I will become a published author when Simon and Schuster releases my debut novel. I love being Jessica Knoll, magazine editor and writer. I want those things to define me—not being a mother, which sometimes seems to override every other priority and accomplishment.

I wish I could hold on to my current identity indefinitely. But for the first time at my annual appointment, my gynecologist brought up children. The real difference between 29 and 30, it turns out, is that your gyno is suddenly more concerned about your dwindling eggs than your STD status.

"I'm not really into kids," I said, grimacing at the ceiling as she finished the exam.

"Nothing wrong with that," she said. She motioned for me to sit up.

"I think I'm going to have one anyway." I scooted forward and clutched the paper robe tightly across my chest. "But I've never heard of anyone deciding to have a child when she doesn't really want one."

"Don't wait to want one," she advised me. "You may be the type of person for whom this will be a logical decision, not an emotional one. Just say to yourself, 'A few years from now, I'm going to do it.' You may not feel happy about it, but there isn't necessarily anything wrong with that."

Here's something I've never told anyone before: Babies give me pause, but a paper-thin sliver of excitement slices through me when I think about having a teenage daughter. I picture us going shopping together, and her coming to me when she needs advice about boys and applying for her first internship, and about how to navigate girl world, which is rife with emotional land mines.

This may seem baffling to some. The consensus is that teenagers are insufferable. I had been a nasty piece of work myself at times (sorry, Mom and Dad). But I imagine my rose-colored fantasy of jeans-swapping and late-night confidences exchanged over hot chocolate is not unlike the expectations many of my friends had about their own spindly pink newborns. They're always so shocked that the first few years of motherhood are hard—and scary. "How did you think it would be anything but?" I wonder.

But there's more to this longing than shopping for prom dresses. I went through a painful phase as an adolescent. Recalling it now makes me feel raw and exposed, tender to the touch. I'm flush with emotion at the idea of being there for my daughter, or any teenage misfit, really, when she experiences her own set of growing pains. Back then, I hid my wounds because I thought no one would understand, because I figured there was no refuge from the crushing loneliness. I think many of the adults in my life suspected I was hurting, but they were afraid to ask what was wrong, afraid of what the answer would be. I won't be the adult who is afraid to ask.

And maybe, one day, when my daughter tumbles into young adulthood and finds herself wrestling with a big life decision, I'll tell her a story that's a little different from the one my mother told me. Mine will sound something like this: "I never got to the point where the desire to bring a baby into this world was suddenly shimmering and all-encompassing, where I turned to your father and surprised us both by saying, 'I want one.'" Rather, I'll tell her that I arrived at a place where I could say, "I'm so happy I didn't wait to want one. Otherwise, I wouldn't have you."

The story will be better than my mother's, because it will be all mine.